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The Perfect Stationery:A Study of the Properties of Different Paper Materials |
Paper-making is a ancient craft, dating back as far as Second Century China. Being relatively light, tough, and inexpensive, paper has since become the most popular surface/medium for printed material. Having at times been made from such various materials as silk, reed, fishnets, and other plant fibers, paper today, as it has been since soon after the advent of the printing press, is made exclusively from reconstituted plant fibers (pulp), pine wood being the most common. In our project/ experiment, we sought to test various plant fibers in order to determine if the preference towards pine wood pulp is justified.
Our Experiment
In our experiment, we compared the properties of various papers, some commercial
paper and some papers we constructed ourselves. We made our own paper from
various pulp materials, including cotton, processed pine, recycled paper,
and hemp. (We had original hoped to include reed, but later determined that
the reed would entail too much hassle.) The properties which we tested included
the strength (resistance to tearing), weight, absorbency, and effectiveness
as a surface for photographs. We tested strength by testing the maximum
weight the paper could suspend, weight with a simple scale, absorbency by
measuring the ink bleed on the papers, and effectiveness as photography
paper by making Van Dyke prints with the papers. We hoped to determine which
paper (cotton, pine, recycled paper, hemp, or the commercial pine-paper)
made the best (ie. strongest, lightest, least absorbent) paper.
| Paper Materials: | Equipment: | |
| pine wood pulp | Hollander beater | 12x12" glass plates |
| ( from Bowater Paper Plant) | floating deckle (5x7) | (drying board that the paper will not stick to) |
| beakers (500ml, 700ml) | clock or stopwatch | |
| hemp fiber (Cannabis Sativa) | microscope | blotter for drying the samples |
| (from commercial hemp twine) | wire strainer | small screw clamps (2) |
| fountain pen | ring stand | |
| cotton fiber | (Pilot* Precise V7 Fine Black) | pipette |
| (from processed cotton boards) | Van Dyke solution | pressed flowers (for silhouette image) |
| sodium thiosulfate solution | ||
| brown grocery bags | digital balance | |
| (from Piggly Wiggly grocers) | ultraviolet light box | |
| large plastic tubs | ||
| commercial drawing paper | felts and Pelons* | |
| (Strathmore* Drawing Paper, 300 series, 340-311, 11x14, 70 lb.) | 50g, 100g, 200g, 1k, 2k weights |
"*" indicates brand name
For more information on commercial paper, see Bowater paper plant.
Pulp Beating
First, we tore a sheet of processed hardwood pulp into small pieces of
fiber, weighing in total 140ml, and soaked paper pieces in a tub of water.
We then poured the soaked mass into the 
Hollander beater,
(shown right) fired up the machine, and, over about a 30 minutes period,
lowered the beater blade to a setting of 1.9. Once the cylinder reached
a setting of 1.9, we let the pulp beat for 2 minutes. We then cleaned the
beater. Next, we tore into small pieces two brown grocery bags from Piggly
Wiggly grocers . We soaked the paper in a tub of water and put the soaked
mass into the beater. We beat the brown paper bag particles, reducing the
setting from 20 to 2 at a rate of 1 per 50 sec. At setting 2, we let the
pulp be beaten for two minutes. We cleaned the machine. Next, we tore white
cotton boards into small pieces. We soaked the cotton in a tub of water
and put the soaked mass into the beater. We beat the cotton , reducing the
setting from 20 to 2 at a rate of 1 / 50 sec. At setting 2, we let the pulp
be beaten for two minutes. We cleaned the machine. Lastly, we took hemp
twine and boiled it in diluted ammonia. We separated the hemp twine into
its three constituent strands and then put the hemp pulp in the beater and
beat it. We lowered the beating setting to 1.3 at a rate of 1.5/ minute.
We let the beater beat the pulp for 40 minutes at setting 1.3. Judging by
the size of the hemp strands the pulp was not beaten enough, so we beat
the pulp again at 1.9 for 45 minutes the next day. We then cleaned the beater.
We stored the beaten pulp (called slurry) in water in plastic tubs.
Couching Process
We set a floating
deckle in a large plastic tub filled with water. We poured 700ml of
the first pulp material into the floating deckle (right), submerging it
in the tub. Patting down the pulp and rotating the deckle in the water,
we took care to make consistent the thickness of the pulp as best we could.
We took the deckle out of the water, separating the parts, and couched the
pulp onto an absorbent cloth. We repeated this process for each of the materials,
making three 5x7 inch sheets of paper each for the cotton, processed pine,
and recycled paper bag and five sheets for hemp. We stacked these sheets
of paper on one another, with large square plates of glass and Pelons between.
We let these sheets dry overnight. We removed the dampened Pelon the next
day and placed on a dry Pelon, and let the papers dry further.
Weight, Strength, and Ink Tests
We weighed each paper sample on a digital balance, recording the mass
of each sample. We then determined the average mass for each paper material
so that we could compare the papers.
In order to test the strength of each paper, we had first to construct a specialized suspension apparatus (shown right). We used a pair of scissors to cut 1x5 inch wide sections from each paper (sample #2). On either end of these strips, we attached a screw clamp. We placed between the paper and clamp two ends of a broken Popsicle stick to prevent the paper from tearing at the clamp rather than at the weakest point in the strip. We attached one clamp to an arm of the ring stand and suspended small weights from the other clamp below. The weights sat on a 50g hook (the recorded mass of the weights included this book). We added more weights to the hook until the paper strip ripped in two.We also calculated the average strength to mass ratio.
To determine the absorption factor of the papers, we measured the ink bleed that resulted from writing on the surface of the paper. We used a Pilot precise ink pen to write the phrase "this is a test. this is only a test" on each of the five papers (one of each type, sample #1). We examined the bleed with the naked eye to note qualitatively the differences in the bleed. We also measured the bleed under a microscope to compare quantitatively the bleed.
Van Dyke Printing
For this portion of the testing, we used a pipette to apply 10mL of the Van Dyke solution to the surface of one sheet of each of the four types of paper, spreading the solution as evenly as possible on the paper. We then exposed the papers to ultraviolet radiation for seven minutes in a sealed ultraviolet light box. After exposing the sample sheets, we submerged the samples in a small tub filled with sodium thiosulfate solution, a fixer. We then rinsed the samples in water, and placed them on the drying rack until they were dry.
Material Sample No. Mass (g) average mass Strength Test No. Strength Test (g) Avg. Str. to Mass Ratio (Sample #2 for each) Bleed (mm)
Absorbency Observations Recycled Paper 1
7.792 9.34
1
1850
177.5g/g pulp
0.5
absorbency similar to that of commercial paper 2
10.45 2
1900
3
9.778 3
1800
Pine Wood 1
13.72 15.81
1
1050
57.66g/ g pulp
0.66
heavy absorbency, sponge-like 2
17.632 2
1050
3
16.08 3
950
Cotton 1
11.765 13.386
1
1750
114.5g/ g pulp
0.83
more abrasive surface resulted in less absorbency 2
15.865 2
1800
3
12.53 3
1900
Hemp 1
3.93 4.255
1
8100
2453g/g pulp
0.5
absorbency similar to commercial paper 2
3.94 (3.93)
2
10400
3
3.82 3
10500
4
5.33 Commercial 1
3.383 3.383
1
4850
1330.1g/g pulp
0.33
medium absorbency 2
4150
Van Dyke Prints Material Print Results recycled paper poor print--monotone, little contrast (brown surface) cotton good print--good detail, good contrast* pine poor print--no detail, bad bleed of color hemp poor print--very faint color, little detail* commercial good print--great detail, good contrast *
brown staining is result of poor solution and uneven application
Van Dyke Prints
Hemp Pine Recycled Cotton
Pulp Beating and Couching
The pulp beating process overall was successful. However, the hemp fibers proved particularly difficult to prepare. Unlike all the other materials from which we made paper, the hemp was the only unrefined material. The twine first had to be boiled in dilute ammonia to remove the lignin, and then separated and unwound into three constituent strands, a tedious process. We determined that the hemp twine ought to have been first cut into three inch long pieces before boiling them in dilute ammonia, making the unwinding easier. Also, upon reading the literature on hemp, we discovered that hemp contains very low amounts of lignin, thus making the boiling in ammonia unnecessary. Being unrefined, we believed that beating the hemp for two minutes at a beater setting of 2 would not be sufficient. Even after beating the hemp fiber for forty minutes at setting 1.3, we notice the presence of fibrils longer than in any of the other materials (which we now understand as a characteristic inherent in hemp). Judging that the hemp was not sufficiently beaten, we beat the hemp even longer. After the further 45 minutes of beating at 1.9, the fibers were still rather long; we then decided to couch the hemp.
The couching process presented no problems. The drying of the papers after couching on a large glass mirror produced the flattest paper samples. However, some of the paper samples, particularly the hemp, which had been taken off the mirror and placed back on, tended to curl during the drying process. Re-immersion in water and re-drying worked well to correct the curl in the hemp.
The papers made during the experiment exhibited varied textures and stiffnesses. The cotton and pine were thicker papers, pliable yet sponge-like; their thickness, or caliper, was much greater than the other hand-made papers. The recycled paper had the texture and stiffness akin to recycled cardboard. The hemp paper appeared leathery, rough, and stiff. Hemp produced a thinner and slightly less opaque paper.
Weight, Strength, and Ink Tests
There occurred nothing unusual in the weighing of the papers. Papers of the same material were similar in weight but not exactly. The variance in the weights of papers of the same material can be attributed to the imprecise measurement and handling of the pulp in the paper making process and to the general inconsistency of the pulp itself. The commercial paper and the hand made hemp paper were the least heavy.
Similarly, the lack of uniformity in the pulp also accounted for the differences in strength observed in the strength test for strips of the same sheet of paper. The hemp paper by far was the strongest paper, stronger than the commercial paper, and had the highest strength to weight ratio (2453.4g/g pulp).
In the ink test, the commercial paper performed the best, with the smallest bleed, yet the bleed in the recycled paper and the hemp was not much worse. Ink on the cotton paper was more difficult to apply; the coarser material prevented fluid application (i.e. writing). Yet, ink on the cotton paper also bled more. We believe that commercial version of the cotton and hemp would produce even better results than those we tested.
Van Dyke Photography Results
Each of the papers reacted to the Van Dyke process differently, not just with regard to the quality print on the paper, but also with regard to the effect the process had on the paper's integrity. In the pine paper, in particular, the structural integrity of the paper's hydrogen bonds was compromised upon immersion in the sodium thiosulfate; large bits of paper broke off during the process. The resulting print images for these two papers were broken, and they both contained very little detail. The cotton paper also became very flimsy and became easily susceptible to tearing, necessitating careful handling. The hemp paper did not appear to absorb the Van Dyke solution as well as the other paper samples. The print on the cotton paper was by far the best print of those papers we made-- it was detailed and consistent. The recycled grocery bag paper created a very monotone print with little variation in value. This characteristic can be attributed to the brown color of the paper, which caused the print to appear faded in comparison. The hemp paper did not make a detailed print. The print, we believe, was partially washed off by the water rinse, causing the print to fade in some areas.
Overall, the hemp pulp made for the best paper material. Hemp made for
the strongest and lightest paper, and, though hand-made, the hemp paper
performed nearly as well as commercial paper in the ink test. However, the
hemp paper did not function well as a Van Dyke print; unlike pen ink, the
Van Dyke solution did not absorb thoroughly enough. The cotton paper performed
much better for Van Dyke prints. The success of the hemp paper, however,
may correspond to the unusually long beating time. It may thus be misleading
to compare the hemp with the other papers because of this discrepancy. Still,
the hemp paper functioned nearly as well as the commercial wood paper in
the ink test and better than commercial paper for its strength to mass ratio,
which might suggest more than does its comparison to the hand-made other
papers. The other home-made papers, as a group, performed surprisingly poorly,
particularly the pine wood pulp. Though beaten for the same amount of time
as cotton and recycled pulp, pine wood paper was the weakest, heaviest,
most absorbent paper made. Based on our experiment, it appears that the
preference towards pine wood pulp as a paper material is not justified.
Biermann, Christopher J., Handbook of Pulping and Papermaking, 2nd ed., Academic Press, San Diego, 1996.
Dawson, Sophie, A Hand Papermaker's Source Book , New York : Design Books, 1995.
Hunter, Dard, Papermaking: The History and Technique of an Ancient Craft, Dover Publications Inc., New York, 1947.
Library of Congress, Papermaking: Art and Craft; an Account derived from the Exhibition presented in the Library of Congress, Washington, D.C. 1968.
Roberts, J. C. (John Christopher), The Chemistry of Paper, Cambridge : Royal Society of Chemistry, c1996.
Toale, Bernard, The Art of Papermaking, Davis Publications, Inc., Worcester, Massachusetts, 1983.
Weidenmuller, Ralf, Papermaking: The Art and Craft of Handmade Paper, Thorfinn International Marketing Consultants Inc., San Diego, 1984.
Twinrocker, a paper material supplier
Information on making Recycled Paper
FAQs on how you can make hand-made paper
Arts and Craft Forum on Paper Making, a really good recipe for home-made paper.
Wooky Hole Paper mill, a paper mill in England which still makes paper by hand, including hemp paper.
To get a look at large-scale paper making, link to the Bowater Papermaking Plant .
Or to learn more about the paper making industry, link to the SkogsSverige Forestry Sector. This site has a great diagram of an industrial paper making machine.
A diagram of the entire wood pulping process and a description of the modern paper making industry.
Hempland.com, a vendor of hemp goods.
A very interesting study of hemp as an alternative fiber source, HEMP: A discussion paper on hemp and its potential uses as an industrial resource in Australia, prepared for Mr. Eoin Cameron, MP, Deputy Chair of the House of Representatives, Standing Committee on Environment Recreation and the Arts, by Mica Brechin Stark, University of New Hampshire, PARLIAMENT OF AUSTRALIA. This is a fantastic site; it delineates in great detail the benefits and uses of hemp fiber.
SWT's personal denunciation of the paper industry's preference of pine over hemp as a paper material. The Conspiracy Theory.
For more information on making paper by hand, please return to the Chemistry and Art web page on hand made paper.
Also see Amanda Spann's, a fellow classmate's, page for more background on paper and its history.